СЕВОФЛУРАН

Описание

Sevoflurane is a rapidly acting, potent inhalation anesthetic with rapid uptake and and elimination. While somewhat less potent than halothane, sevoflurane does not induce arrhythmias and reportedly has no effect on renal function.

Химические свойства

Clear, colourless, volatile liquid.

Определение

ChEBI: An ether compound having fluoromethyl and 1,1,1,3,3,3-hexafluoroisopropyl as the two alkyl groups.

Биологические функции

Sevoflurane (Ultane) is the most recently introduced inhalation anesthetic. It has low tissue and blood solubility, which allows for rapid induction and emergence and makes it useful for outpatient and ambulatory procedures. It has the advantage of not being pungent, a characteristic that permits a smooth inhalation induction, and is particularly useful in pediatric anesthesia.
Hypotension is produced by sevoflurane as systemic vasodilation occurs and cardiac output decreases. Since it does not directly produce tachycardia, it is a useful alternative to consider in patients with myocardial ischemia. However, a concern for reflex-induced tachycardia remains.
Sevoflurane undergoes hepatic biotransformation (about 3% of the inhaled dose), and it is somewhat degraded by conventional CO₂ absorbents. The degradation product from the absorbent has been reported to be nephrotoxic, although the report is controversial and not substantiated by more recent studies. Sevoflurane’s actions on skeletal muscle and on vascular regulation within the CNS are similar to those described for the other halogenated hydrocarbon anesthetics.

Общее описание

Sevoflurane is a volatile, nonpungent, nonflammable, andnonexplosive liquid with a boiling point of 58.6°C. Theblood:gas partition coefficient is 0.65, the oil:gas partitioncoefficient is 50, and the MAC is 2.1%. Sevoflurane reactswith desiccated carbon dioxide adsorbents, to produce compounds(A and B) with known toxicity . The typeof CO₂ absorbent used, the temperature of the absorbent,and the duration of exposure can influence the degree towhich sevoflurane breaks down. The major breakdownproduct, compound A, pentafluoroisopropenyl fluoromethylether, (PIFE, C₄H₂F₆O) has been studied extensively.Compound A is nephrotoxic in rats and nonhuman primatesand remains a theoretical risk to humans. As discussedpreviously under the stability of inhaled anesthetics,sevoflurane breakdown by CO₂ absorbents generates heatand has resulted in sporadic operating room fires.

Клиническое использование

Sevoflurane has been shown to cause epileptic changeson EEGs and case reports of seizures during surgery, especiallyin children, have been reported.